The Canadian tar sands are the world's third largest known oil reserve. The mix of bitumen, sand and clay underlays much of Athabasca in Alberta. The exploitation of the tar sands to make synthetic oil, is the most environmentally destructive project on the planet. The oil companies are responsible for the second fastest rate of deforestation on the planet, second only to the Amazon rain forest. The Boreal forest being ripped down is not only a huge carbon sink and part of the lungs of the planet, but supports amazing biodiversity. All this is lost when ripped down. The resulting oil produced has three times the carbon footprint of conventional oil, due to the vast quantities of gas used to heat water, to extract the bitumen from the sand. This highly polluted, toxic water is then put in massive unlined tailing's ponds, that leach their toxins out to the wider environment. The first Nation communities of Fort McKay and Fort Chipewyan that are downstream of the tar sands mines are suffering very real health problems, including high rates of rare cancers.